We don't need them. They'll never see things our way, no matter what. Let them go.

It's a new Israeli approach which borrows from the very worst of our aging instincts. It says: We're moral, our enemies are out to exterminate us along with our state, that's all you need to know. No modifications necessary. Stay the course. Concede nothing. Ease no siege. Give no ground. Ever.

It is a radical redefinition of Postmodern Zionism, this time from the right. Over the past weeks, it's been test-run in our relations with Turkey, with the Goldstone Commission, with Mahmoud Abbas - and with consistent results.

Now it's about to be tried on North American Jewry, some 6 million strong, a community at a critical crossroads, one that will have lasting and - if mishandled - dangerous consequences for Israel.

The opening shot was fired this month by the former chairman of the Governing Board of the World Jewish Congress, Isi Liebler, who declared it "our obligation to confront the enemy within - renegade Jews - including Israelis who stand at the vanguard of global efforts to demonize and delegitimize the Jewish state."

"Such odious Jews can be traced back to apostates during the Middle Ages who fabricated blood libels and vile distortions of Jewish religious practice for Christian anti-Semites to incite hatred which culminated in massacres," Liebler wrote in the Jerusalem Post. "It was in response to these renegades that the herem [excommunication] was introduced."

Citing the example of Jewish communists who applauded Stalinist executions of fellow Jews on trumped-up charges, Liebler added, "Like their contemporary counterparts, some of them attempted to depict themselves as devoted Jews championing 'world peace.'"

Among these counterparts, it develops, is J Street, the new dovish lobbying organization which describes itself as pro-Israel and pro-peace. Writing ahead of J Street's first annual national conference, which begins on Sunday in Washington, Liebler argued that although J Street and other U.S. Jewish groups critical of Israel may describe themselves as Zionist, "their prime objective is to pressure the U.S. government to use 'tough love' against Israel - a euphemism for demanding that the Jewish state make further unilateral concessions to neighbors pledged to its annihilation."

Israel's official response to J Street, which though less than two years old has been described as a counterweight to AIPAC, this week went from chill to cold-shoulder.

Months after inviting Ambassador Michael Oren to address the conference, J Street last week renewed its request. It noted research which has shown younger Jews increasingly alienated from the Jewish community and from Israel, and increasingly questioning many of Israel's right-wing policies, public statements, and actions.

The erudite, often outspoken Oren had been uncharacteristically mum in response to the request, despite, or perhaps because of, the long list of some 150 U.S. senators and members of Congress which J Street has published as honorary hosts of a gala dinner during the conference. The list has apparently dismayed both AIPAC and conservative commentators.

When an answer finally came, it came in the form of a slap. "In response to the question about J Street's invitation to participate in its conference, the Embassy of Israel has been privately communicating its concerns over certain policies of the organization that may impair the interests of Israel," the embassy said in a statement, an apparent reference to such J Street positions as support for the Obama administration's push for an absolute settlement freeze, and the group's opposition to immediate sanctions against Iran.

"Accordingly, the embassy will send an observer to the conference and will follow its proceedings with interest."

In rebuffing the invitation, the ambassador has erred gravely. Instead, he should have shown up, spoken forthrightly on the ways Israel's government views the future differently from J Street and the other dovish groups co-sponsoring the gathering. Together, they represent a growing segment of the future of U.S. Jewry, a community with which Israel cannot afford to lose touch.

To slight the conference is to dismiss the deep love of Israel felt by many of its critics abroad. To send a low-level diplomat in place of the ambassador sends a message which in some respects can only please Isi Liebler, and the subtext of his message: These doves, they're not really pro-Israel. They can't be. They're doves. And they're not really Jews. How could they be? Not only are they doves, most of them aren't even Orthodox.

Liebler, meanwhile, has another plan. Because Benjamin Netanyahu is "currently riding a wave after his superb United Nations address," Liebler writes, he should convene a global Jewish solidarity conference of Jewish leaders, opinion makers, philanthropists and activists "in order to demonstrate the unity of the Jewish people."

And what of J Street and the spectrum of Jewish leftists and peace advocates? The world unity conference would deal with them as well. According to Liebler, "in addition to encouraging millions of Jews in the Diaspora who remain committed to Israel to become more actively engaged in our struggle, such a gathering would also provide an opportunity to exorcise the renegades from our midst."

Haaretz.com, the online edition of Haaretz Newspaper in Israel, and analysis from Israel and the Middle East. Haaretz.com provides extensive and in-depth coverage of Israel, the Jewish World and the Middle East, including defense, diplomacy, the Arab-Israeli conflict, the peace process, Israeli politics, Jerusalem affairs, international relations, Iran, Iraq, Syria, Lebanon, the Palestinian Authority, the West Bank and the Gaza Strip, the Israeli business world and Jewish life in Israel and the Diaspora.